This invention relates to thermal identification, and more particularly, to a thermal image identification marker utilizing infrared (IR) energy from 1000-1400 nanometers.
The inability of reconnaissance to determine friend or foe in low light or total darkness is a major failing in battlefield and law enforcement operations. The worst effect is that fratricide (the inadvertent killing of friendly forces by other friendly forces) occurs, and at best is a waste of time and resources attempting to confirm identification. Accurate intelligence allows deployment effort to be maximized and focused.
Present marking and identification systems are limited to either Near IR range (1010 nano meters or less) beacons for use with night vision glasses or thermal panel identification marking equipment. Present thermal panel identification marking equipment is passive and provides identification by temperature or emissivity differences between adjacent areas and the marking equipment. Passive marking equipment is easily masked by surrounding operations, and is difficult to differentiate from adjacent targets.
There is a requirement for thermal (heat emitting) devices for military and law enforcement purposes to enable specific identification of distant objects, people, vehicles or positions by means of ground or air mounted thermal imaging cameras in spite of ambient thermal noise. Anti-fratricide protection is one very important application for such devices.
The present invention relates to beacons, and more particularly to a beacon for use as a marker and identifier in conjunction with night vision applications and situations.
However, in the areas of law enforcement and military applications there is a need to provide marker and identification beacons which operate in the wavelength band of 1 to 13 microns to clearly identify friend from foe, this being achieved without anything being seen by the naked eye.
Thermal imaging cameras have now reached a high state of development and produce clear images with clear contrast and magnification across a wide thermal gradient range of temperatures between hot and cold surfaces.
There are two approaches to thermal beacons, active and passive. The active approach uses a tripod with a controlling motor and either an electrically driven head or a gas driven head. The electrically powered head would be used in situations where sufficient power is available to drive the active emission part of the beacon, such as a main power feed or a vehicle battery. The gas driven head would be used in stand alone situations where power is not readily available. In either case, the active element can be rotated causing the unit to appear to flash to an observer with a thermal detection device.
The passive approach uses material which is thermally reflective. Passive technology requires a significant size panel when deployed to provide a surface detectable from 3,000 meters. However, the reflecting panel must be compact for transportation and deployment. To meet these conflicting requirements, it is necessary to construct a folding system which allows the reflection panel to be collapsed and has holes, slits or slots to accommodate wind and prop and helo wash.
In prior applications, applicants have described various forms of beacons which produce a flashing heat output. There is a limitation in these beacons in that they need considerable power in order to operate effectively. From an operational point of view, the power requirement can make them undesirable for certain applications.